since ancient times? From generation to generation, human beings have almost worshiped the light. In ancient Greek mythology, Apollo, the sun god, was second only to Zeus, the god of gods. The growth of everything depends on the sunshine. It can be said that it is from this simple observation that human beings realize the significance of light to life and try to introduce it into the means of treating diseases.

The earliest way to treat diseases with light was very primitive. The ancient Maya exposed patients with skin diseases to the sun, believing that the sun god could remove evil spirits from patients. According to the ancient geomantic theory in China, it is very important to make the owner healthy and happy.

however, in the development of modern medicine, optics has not been paid attention to by people, and it has long been on the edge of medicine. It was not until the emergence of Danish medical scientist Finson that light really became a formal medical means.

exploration of smallpox disease

Ryberg, niles? Finson was born in Toles Port, the capital of the Faroe Islands in Denmark, in 186. As the ninth child in the family, he is the most beloved little guy in the family. In 1876, at the age of 16, Finson finished his studies in Denmark and returned to his grandmother's house in Iceland. Here, Finson completed his middle school study. Because of his excellent math and biology achievements, he was admitted to the pharmacy major of Copenhagen University in Denmark, and his main direction was to improve the medical treatment of smallpox. Suffering from echinococcosis, he felt with amazing scientific intuition that the light that accompanies us every day may be a brand-new means to treat smallpox. Finson repeatedly consulted the relevant literature and found that as early as 1877, two British scientists, Downs and Brent, had studied the role of sunlight in medical care. They believed that sunlight did have a curative effect on some diseases. This is because ultraviolet rays or other components in sunlight have a bactericidal effect on bacteria, but due to the research conditions at that time, The two scientists failed to specifically point out which kind of radiation has a significant killing effect on which bacteria, and did not further explain which diseases can be treated by optical therapy, so this research result has not attracted much attention from the medical community. In 189, Finson received a doctorate in medicine from the University of Copenhagen. After graduation, he stayed at his alma mater as an experimental teaching assistant of anatomy. Two years later, in order to devote more time to scientific research, he resolutely quit his comfortable and well-paid job at his alma mater and devoted all his energy to the research of phototherapy. In the process of research, Finson gradually discovered such a rule, because the time and intensity of light with different wavelengths in the spectrum are different, the influence on the organism is also different. Through experiments, he found that the purple light with high refractive index, such as blue-violet light and ultraviolet light, which are called chemical light in the natural spectrum, will cause smallpox patients to have high fever and blisters on their skin, leaving pockmarks in the light and losing their lives in the heavy; The other end of the spectrum-red light and infrared light with low refractive index belong to thermal rays, and their chemical effects are very small, which can not only speed up the recovery of smallpox, but also prevent complications caused by normal illumination. Therefore, Fensen placed the smallpox patient in a red room for light radiation treatment. The patient not only saved his life, but also left no common pockmarks after smallpox rehabilitation. According to these valuable experimental data, Fensen invented the "Fensen lamp" named after himself. This instrument is hung high in the treatment room and emits light with a specific wavelength to treat smallpox patients. In 893, Finson published this research result, which brought hope to many smallpox patients in the world.

Research on lupus erythematosus

Finson found that light can cure smallpox. Shortly after the secret, he went to a seaside fishing village in Iceland to recuperate due to illness. He found that a terrible infectious disease was prevalent among local fishermen, which was a very refractory skin tuberculosis, mainly damaging people's facial features and cheeks, and most of the patients were killed because they could not be treated. Faced with this situation, as a doctor, a strong sense of responsibility made Fensen put his illness and recuperation aside, thus turning to the study of optical therapy for lupus erythematosus. After the research, it was found that although lupus erythematosus and smallpox are two completely different diseases, they both show serious skin damage in patients' clinical symptoms. Therefore, the idea of treating lupus erythematosus through optical therapy is theoretically feasible! However, after all, there are differences between the two. The treatment of lupus erythematosus requires more chemically active ultraviolet rays, not infrared rays for smallpox. In November, 1895, Finson conducted his first experiment in Copenhagen Power Plant. An engineer in the power plant who was seriously ill and could not be cured for a long time became his first patient. After a period of phototherapy, the hopeless engineer miraculously recovered, and the scar on his face basically healed and faded. Finson's first experiment was a great success. In 1896, Finson published a paper entitled "The application of concentrated chemical light in medicine". At the beginning of 1896, only two patients were willing to receive Finson's phototherapy. By 1897, Finson independently operated a laboratory built in a humble hut next to a hospital, and 15 patients were treated by him at the same time. As he cured more and more patients, Fensen became more and more famous. In that year, the mayor of Copenhagen personally allocated funds to help him set up the Fensen Institute of Optical Medicine. Fensen has brought back the hope and gospel of life to patients with smallpox and skin tuberculosis. People call him "the magic doctor who uses light to treat". In 1899, the Danish government awarded Finson the title of "Knight" in recognition of his outstanding contribution to medical progress, which is a very high honor in Denmark. In 19, a doctor friend of Finson introduced Finson's research results to medical researchers from all over the world at an international medical forum. The news that lupus erythematosus, a once incurable disease, was conquered by a Danish medical scientist caused a sensation at the conference. Finson became famous all over the world and became one of the most prestigious dermatologists at that time.

On December 1th, 193, it was a great day in the history of Danish science. The Royal Swedish Karolinian Institute of Medicine announced that Finson had decided to award him the Nobel Prize in medicine or physiology that year because of his outstanding achievements in the research of overcoming lupus erythematosus, which was also the first Nobel Prize in Danish history. Thus, Finson was called the hero of the motherland by Danish nationals, but at this time, Finson did not appear on the podium. As a result of many years' work, he knows that he is terminally ill and has little time left, so he should continue his research bit by bit. Regrettably, just one year after winning the Nobel Prize, on September 24th, 194, Finson left his beloved laboratory forever due to the deterioration of his illness. Before he died, he donated 57Y kronor of the Nobel Prize he won to the Institute of Optical Medicine as a fund, and donated another 5, kronor to a sanatorium for heart and liver diseases founded by him. Finson's last wish is to donate his body to study echinococcosis. A month later, Finson's body was placed in a church in Denmark, and Danish nationals held a funeral for him, which was second only to the king, to commemorate Finson's great contribution.

the ups and downs of phototherapy for a hundred years

However, just after Fensen's death, the research of phototherapy had to come to a standstill because Fensen lamp therapy was gradually found to have serious side effects. Even in 1895, physicist Roentgen accidentally discovered X-ray in the study of exploring the nature of cathode ray, and became the first Nobel Prize winner in physics. X-ray was only used as a diagnostic means, not a therapeutic means. With the discovery of a series of antibiotics, especially the invention of Fleming penicillin in 1928, mankind has entered a new medical era of unprecedented dependence on drug treatment. Whether it is tuberculosis or lupus erythematosus, these incurable diseases in the past are vulnerable to the new anti-tuberculosis combined drug therapy and will be defeated. However, under this prosperous time of seemingly conquering the disease in an all-round way, what is hidden is the fatal mistake of human beings. Nearly half a century has passed, and there are more and more kinds of drugs, but people are horrified to find that diseases are gradually escalating in the constant renewal of drugs. Faced with cancer and AIDS, we still have nothing to do. People began to reflect on the shortcomings of the treatment methods that have been too dependent on drugs for half a century, and re-focused on the long-forgotten optical therapy.

First of all, the medical treatment using laser stands out among the optical therapies. In the summer of 196, American scientist Mayman made the world's first ruby laser, and since then, a completely novel light source has been born. Laser is a kind of pure artificial light that does not exist in nature. Its light, electricity, magnetism, heat, mechanical pressure and biological stimulation make the complicated treatment process of many diseases simple and effective, which opens up a new field for the diagnosis and treatment of diseases. Because of its high directivity and precision, in 1961, just one year after the invention of the laser, Zeret and others announced the first medical experimental study of laser application in ophthalmology. Subsequently, the clinical application of laser entered a period of rapid development. In 1963, Goldman and others effectively treated skin diseases with laser. In 1966, people cut the skin with a laser knife focused by high-energy laser. Later, vocal cord resection and thoracotomy were performed, and laser surgery was popularized. For example, laser scalpel is used for cosmetic surgery, orthopedic surgery, spot removal and nevus removal, treatment of dental caries, fat removal, induced abortion, tumor removal, hemorrhoid treatment and acute deafness.

The main mechanism of the phototherapy used by Fensen in those years was to kill irradiated cells by using the thermal effect of infrared rays or the photochemical effect of ultraviolet rays, so as to kill pathogenic cells. However, the disadvantage that comes with this is "grasping the beard and eyebrows". Although harmful cells are killed, healthy tissues and cells are also damaged at the same time, which is also the case later. The main reasons for quitting the medical technology stage. However, with people's research on a "photo-allergy phenomenon", optical therapy has another day of "reappearing in the rivers and lakes". In 1887, the German scholar Ruanbi first discovered that when mice were injected with certain dyes subcutaneously, their skin would be red and swollen after illumination, indicating that they were damaged. In 1913, after injecting himself with 2 mg of crude hematoporphyrin, Meyer had a strong photosensitivity reaction, which lasted for several months. This is the first time that human beings have observed the photosensitive phenomenon of human skin caused by hematoporphyrin. Simply put, photosensitive phenomenon is the process that foreign photosensitizers are metabolized through an "excitation-reduction" path under the action of light after entering cells. However, a large number of reactive oxygen species (ROS) and other substances produced with this reaction have toxic effects on cells, so they can kill cells that have absorbed photosensitizers. According to this principle, in the 194s, someone put forward the concept of "PDT", which was used in the clinical treatment of tumors, that is, according to the different half-lives of photosensitizers in different tissues and the characteristics of tumor-friendly tissues, the concentration of photosensitizers in tumor tissues was higher than that in normal tissues around them after a certain period of time, and then the targeted killing of cancer cells was achieved by light irradiation. Compared with Fensen's therapy, photodynamic therapy has a high degree of orientation and accuracy, which can accurately locate tumor cells, so the corresponding side effects are also small, and it can be applied to various patients who are not suitable for surgery and other treatment methods. Because of the above advantages, photodynamic therapy has attracted the attention of the medical community as soon as it was put forward, and it is regarded as a brand-new medical technology revolution. Since 195s, photodynamic therapy has been comprehensively introduced into the early diagnosis and treatment of various superficial tumors. After the invention of laser, due to the use of high-energy laser beam instead of visible light, the scope of application of photodynamic therapy has been greatly expanded.

In p>1996, the American Instrument and Drug Administration (FDA) officially approved it for clinical use, and in 1997, FDA listed it as one of the five basic methods of tumor treatment (surgery, radiation, chemical drugs, photodynamic therapy, biochemical immunotherapy), which really went to clinic. Looking forward to the future, if more and better specific photosensitizers can be found, the application scope of photodynamic therapy will be greatly expanded, and it may even become one of the treatment schemes for AIDS, not just the treatment of tumors. Its potential in medical care will be further tapped with the support of various new technologies.

Walking through the ignorant ancient times and passing through the Nobel halo overhead in modern times, although it was once close to being forgotten by people, after a hundred years of ups and downs in the medical world, optical therapy has inherited the mantle of Finson, and finally ushered in its second spring at the turn of the new century, blooming its strong vitality.

Editor-in-Chief Sang Xinhua